i am fluent in french as well, so i may be partial…i would say that spanish, italian, and french would be the easiest. the french pronunciation is difficult for the uninitiated, sure, but what i’ve found is that if i don’t know a word in french, i say the english word with a french accent, and it turns out to a be a word (caution: only for more complicated words…words like cat or dog or house are different).
i was totally baffled by dutch, but then, i haven’t tried to study it.
i actually didn’t have that bad a time with japanese - the alphabet (well the easier two of the three) are fairly easy to grasp and the basic grammar isn’t too hard, though i’m told that once you get more advanced, there’s layers of address and such that gets hard.
oh, and latin was pretty intuitive. it’s just the order of the sentence that was hard…subject at the beginning, then indirect object, then prep phrase, then direct object, then verb. ugh.